Update README.md

added links to reference documents

Author: robertoostenveld

README.md

@@ -1,7 +1,12 @@
-# pyEDF
-Python package to read from and write EEG data to European Data Format files. It is implemented in pure Python with very limited dependencies on external packages.
+# pyedf
+
+Python package to read from and write EEG data to European Data Format files.
+
+The EDF standard was introduced in [1992](https://doi.org/10.1016/0013-4694(92)90009-7). The extension of EDF with annotations was first described in [1998](https://doi.org/10.1016/S0013-4694(98)00029-7) and more formalized with the EDF+ standard that was published in [2003](https://doi.org/10.1016/S1388-2457(03)00123-8). The [EDF](http://www.edfplus.info) website describes both standards and discusses implementation details.
+
+Since EDF is such a widely used format, there exist multiple implementations for reading and writing EDF files. Most Python implementations consist of wrappers around the C-code implementation, which makes installation more cumbersome and reduces portability. This implementation is in pure Python with limited dependencies on external packages.
 
 ## See also
+  - http://www.edfplus.info
   - https://github.com/holgern/pyedflib
   - https://github.com/MNE-tools/MNE-python
-